# Black hole and critical mass? [closed]

I keep hearing about big bang, but there are no white holes and no black hole has been observed exploding. So is there a point in which a black hole reaches critical mass?

## closed as unclear what you're asking by CuriousOne, Gert, Prahar, ACuriousMind♦, heatherAug 2 '16 at 12:12

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• I'm voting to close this question as off-topic because it shows no effort at own research. – Gert Aug 2 '16 at 2:33
• Your question implies that you think the Big Bang was like an exploding black hole so just for the record let's make clear that the spacetime geometry of the Big Bang is completely different to the spacetime geometry of a black hole. For more on this see Did the Big Bang happen at a point? – John Rennie Aug 2 '16 at 6:00

Now the problem is that the size of the currently known black holes are all at least 3-4 solar mass. They would require around $10^{50}$ years to evaporate. Compare this to the age of the Universe ($13.7\cdot 10^9$ years).